<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<style>
    #contentDiv{
        width: 1200px;
        height: 800px;
        margin: 0 auto;
        border: 1px solid #000;
    }
</style>
<body>
    <div id="contentDiv">
        <h1 style="text-align: center">权限管理</h1>
        <div style="display: flex">
            <div style="width: 200px;height: 300px">
                <div><a href="user/user.html" target="contentIFrame">用户管理</a></div>
                <div><a href="role/role.html" target="contentIFrame">角色管理</a></div>
            </div>
            <iframe style="width: 800px;height: 600px" name="contentIFrame"></iframe>
        </div>
    </div>
</body>
</html>